How do you solve using the completing the square method #x^2 + 8x = 0#?

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Answer 1 · 2018-04-30T07:00:52

#x=4 or -8#

#x^2+8x=0#
you half the coefficient of #x# and the take away this number squared.

#=>##(x+4)^2-16=0#

so the 8 becomes 4 and #4^2=16#

#=> (x+4)^2=16#

#=> x+4=\pm4#

#=>x+4=4# or #x+4=-4#

#=> x=0 or x=-8#